From 3ec482d15cb986bf08b923f9193eeddb3b9ca69f Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 8 Apr 2019 10:51:01 -0600 Subject: io_uring: restrict IORING_SETUP_SQPOLL to root This options spawns a kernel side thread that will poll for submissions (and completions, if IORING_SETUP_IOPOLL is set). As this allows a user to potentially use more cycles outside of the normal hierarchy, restrict the use of this feature to root. Signed-off-by: Jens Axboe --- fs/io_uring.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'fs') diff --git a/fs/io_uring.c b/fs/io_uring.c index 07d6ef195d05..89aa8412b5f5 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2245,6 +2245,10 @@ static int io_sq_offload_start(struct io_ring_ctx *ctx, goto err; if (ctx->flags & IORING_SETUP_SQPOLL) { + ret = -EPERM; + if (!capable(CAP_SYS_ADMIN)) + goto err; + if (p->flags & IORING_SETUP_SQ_AFF) { int cpu; -- cgit From a89afe58f1a74aac768a5eb77af95ef4ee15beaa Mon Sep 17 00:00:00 2001 From: Jason Yan Date: Fri, 12 Apr 2019 10:09:16 +0800 Subject: block: fix the return errno for direct IO If the last bio returned is not dio->bio, the status of the bio will not assigned to dio->bio if it is error. This will cause the whole IO status wrong. ksoftirqd/21-117 [021] ..s. 4017.966090: 8,0 C N 4883648 [0] -0 [018] ..s. 4017.970888: 8,0 C WS 4924800 + 1024 [0] -0 [018] ..s. 4017.970909: 8,0 D WS 4935424 + 1024 [] -0 [018] ..s. 4017.970924: 8,0 D WS 4936448 + 321 [] ksoftirqd/21-117 [021] ..s. 4017.995033: 8,0 C R 4883648 + 336 [65475] ksoftirqd/21-117 [021] d.s. 4018.001988: myprobe1: (blkdev_bio_end_io+0x0/0x168) bi_status=7 ksoftirqd/21-117 [021] d.s. 4018.001992: myprobe: (aio_complete_rw+0x0/0x148) x0=0xffff802f2595ad80 res=0x12a000 res2=0x0 We always have to assign bio->bi_status to dio->bio.bi_status because we will only check dio->bio.bi_status when we return the whole IO to the upper layer. Fixes: 542ff7bf18c6 ("block: new direct I/O implementation") Cc: stable@vger.kernel.org Cc: Christoph Hellwig Cc: Jens Axboe Reviewed-by: Ming Lei Signed-off-by: Jason Yan Signed-off-by: Jens Axboe --- fs/block_dev.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'fs') diff --git a/fs/block_dev.c b/fs/block_dev.c index 78d3257435c0..24615c76c1d0 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -307,10 +307,10 @@ static void blkdev_bio_end_io(struct bio *bio) struct blkdev_dio *dio = bio->bi_private; bool should_dirty = dio->should_dirty; - if (dio->multi_bio && !atomic_dec_and_test(&dio->ref)) { - if (bio->bi_status && !dio->bio.bi_status) - dio->bio.bi_status = bio->bi_status; - } else { + if (bio->bi_status && !dio->bio.bi_status) + dio->bio.bi_status = bio->bi_status; + + if (!dio->multi_bio || atomic_dec_and_test(&dio->ref)) { if (!dio->is_sync) { struct kiocb *iocb = dio->iocb; ssize_t ret; -- cgit